Problem: $ { \left[\begin{array}{rr}{0} & {3} \\ {3} & {-1} \\ {2} & {-2}\end{array}\right]+\left[\begin{array}{rr}{-2} & {1} \\ {2} & {-1} \\ {1} & {2}\end{array}\right] = {?} } $
Answer: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rr}{0}+{-2} & {3}+{1} \\ {3}+{2} & {-1}+{-1} \\ {2}+{1} & {-2}+{2}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{-2} & {4} \\ {5} & {-2} \\ {3} & {0}\end{array}\right]}$